Systems and methods for modular instrument design and fabrication

ABSTRACT

Modular component mounting systems and methods employ a plurality of members adapted to be interlocked with one another and anchored to an instrument housing. Each of the members comprises a central elongated body, cross-holes extending transversely through the body, beads extending along corners of the body to a position spaced apart from an end of the body defining a key at the end of the body, a channel defined by a surface of the body and a pair of the beads to receive and register with a key of another member, and a fastener receptive orifice defined in the end of the body. A fastener extends though one of the cross-holes of a first member to be received by an end orifice of a second member, interlocking the members and preventing torsional movement by the members relative to one another.

BACKGROUND OF THE INVENTION

Many electronic systems, instruments, and the like must be custom designed and/or fabricated. Such instruments may include processor-based systems, communications equipment, networking equipment, switch matrixes, testing equipment, and the like. Such equipment may be developed to meet specific requirements of a customer and may be one of a kind or small production runs, such as of fifteen or fewer units. However, these same customers expect, or at least desire, an inexpensive solution to such custom applications, provided in a timely manner.

Traditionally, even small run jobs are treated as truly custom jobs that involve custom designing each part including housing and mounting sheet metal, machined parts and the like. This is time consuming and costly. Not only is the cost of a small run of custom parts expensive, overhead related to these custom or small production runs is relatively high as the resulting instrument and its parts require many of the overhead processes and procedures that a mass produced product requires. For example, parts (sheet metal, machined parts, plastic parts, etc.) must be assigned part numbers, documentation must be produced for the instrument and parts, and Engineering Change Report(s) (ECR) and/or Engineering Change Orders (ECO) must be produced and reviewed for parts purchasing and product release. Also, it takes time to fabricate custom parts and the time required to gather all of the custom produced parts may also present problems, particularly where multiple vendors are involved, as is often the case. Oftentimes, it becomes necessary to “chase” after parts to start building a product. When prototyping, or at the beginning of fabrication, it is often found that a custom piece is missing or not made as specified. At this time, it might be determined that a redesign of the instrument is necessary causing further delay and cost. In such cases, it may be necessary to have one or more new pieces fabricated, causing a halt, or at least a delay, in the prototyping process or in product production.

Custom designed instruments often have undesirable qualities. For example the final product may be a relatively “closed” system that requires tortuous cable routing and an inflexibility limiting the ability to make changes or enhancements to the instrument. Custom produced instruments are often cluttered with long cable runs required or with cables routed through sheet metal decks or the like. Additionally, design may be problematic in that the instrument designers may be designing an instrument that uses components that the designers do not have on-hand, and for which the designers may not know the actual, final dimensions or configuration. Although typical custom instrument casing and housing designs employ formed or bent sheet metal parts, attempts have been made to address problems encountered with such sheet metal based structures through the use of open space-frames. These space-frames are typically machined or welded from dimensional metal. However, such frames are typically configured for use in a single instrument design, are costly, and time consuming to fabricate.

Finally, many printed circuit boards (PCBs) employ mounting holes that are placed in a relatively arbitrary layout. Problematically, custom fabricated sheet metal or manual drilling of sheet metal elements must be used to mount PCBs for custom instrument fabrication.

SUMMARY

Embodiments of systems and methods for modular instrument or system design and fabrication may employ a plurality of members adapted to be interlocked with one another and anchored to an instrument housing structure. Each of these integral members has a central elongated body portion, which might have a generally square cross section. Cross-holes may extend transversely through the central body portion, in at least one direction. Bead portions extend along, at least, a pair of corners of the body, to a point spaced apart from an end of the body portion this may result in a key portion of the body being formed at an end of the body. A channel portion is defined by a surface of the body and a pair of the beads, the channel is adapted to register with a key of another member. A fastener receptive threaded orifice is defined in the end of the body. This orifice may be defined by a central cannula extending through a length of the body. Embodiments of the present systems and methods also employ fasteners extending though a cross-hole of a first of the members to be received by an end orifice of a second of the members, interlocking the first and second members and preventing torsional movement by the members relative to one another.

Thus, in use, embodiments of the present systems may be employed by method embodiments that include keying an end of a first member with a channel defined by a second member and receiving a fastener through a cross-hole defined by the second member into the orifice defined in an end of the first member. Securing the fastener interlocks the first and second members, torsionally. Instrument components may then be mounted to the interlocked members to provide a custom fabricated instrument. An orientation of the second member may be selected based on a desired orientation of the cross-holes of the second member, such as may be desired for mounting of the instrument components.

The profile of the present member might be extruded. Alternatively, the present member may be cast. Advantageously, if the present members are made from a heat transmissive material such as aluminum, the member may be used as a heat sink for instrument components. If a stronger member or the like is desired to support a heavy component, such as a power supply, a double or triple truss-like member, or the like, may be made using the present members.

The foregoing has outlined rather broadly the features and technical advantages of the present systems and methods in order that the detailed description that follows may be better understood. Additional features and advantages of the systems and methods will be described hereinafter which form the subject of the claims. It should be appreciated that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present systems and methods. It should also be realized that such equivalent constructions do not depart from the systems and methods set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present systems and methods, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:

FIGS. 1 through 3 are perspective views of various length member embodiments of the present systems;

FIG. 4 is a perspective illustration of a slotted embodiment of a two unit length member of the present systems;

FIG. 5 is an exploded view showing relative deployment of embodiments of members of the present systems in accordance with embodiments of the present methods;

FIG. 6 is a perspective view of an embodiment of a two-member-truss constructed from member embodiments s of the present systems in accordance with embodiments of the present methods;

FIG. 7 is a perspective view of a method embodiment using embodiments of the members of the present systems to act as a circuit board or card guide;

FIG. 8 is a perspective view of a method embodiment using embodiments of the members of the present systems to act as a hinged circuit board mounting structure;

FIG. 9 is an environmental perspective illustration of an instrument employing embodiments of the present systems and methods to mount components; and

FIG. 10 is a flow chart of an embodiment of the present methods.

DETAILED DESCRIPTION

Embodiments of the present systems and methods provide a modular component mounting system that may employ a minimum set of elements. These elements include structural members described below and typical fasteners such as screws, nuts, associated washers, including lock washers, stand-offs and the like. FIGS. 1 through 3 are perspective views of various length member embodiments 100, 200 and 300, respectively, of the present systems. FIG. 1 is a partially fragmented view of member 100 having a “unit” length of at least nine. Herein, a “unit” is the distance between cross-holes 101 in a member, which also corresponds to the overall length of single unit member 300. Also a “unit” as used herein may be viewed as the distance from the mid-points between cross-holes 101, which corresponds to the configuration of single unit member 300. For purposes of illustration, members 100, 200 and 300 of FIGS. 1, 2 and 3 are illustrated as having lengths of at least nine units, two units and one unit, respectively. However, as one of ordinary skill in the art will appreciate, members of the present systems can be of any number of units in length, or fractions thereof. FIG. 4 is a perspective illustration of a slotted embodiment of a two unit length member of the present systems. However, a slotted member may also be of any length, with one or more slots being of any of various lengths.

Each of integral component mounting members 100, 200, 300 and 400 comprise a central, generally elongated, body portion 102. In embodiments of the present systems body portion 102 has a generally square cross-section. Body 102 may be extruded from a generally rigid material such as aluminum or steel. Advantageously, aluminum can be extruded easily and it has other desirable properties. For example, aluminum is lightweight, inexpensive, easy to machine and has very good thermal conduction properties. Relative to aluminum, steel is heavier, but it is stronger in the sense of having a higher modulus of elasticity, but steel would, in most cases more likely, be more difficult to extrude and machine. Additionally, it is within the scope of the present systems and methods that the member may be formed in a number of other manners. For example, the members may be injection molded from plastics, steel, other alloys or ceramics; formed from a composite material using various methods as are known in the art of composite materials; or cast from any number materials such as aluminum, steel, or various plastics or from other materials not particularly well suited for extrusion such as magnesium, epoxy or urethane. Cast or molded members may require less machining than extruded members, for example cross-holes 101 may be cast or molded into a member. However, material that cannot be tapped or otherwise formed or machined to provide relatively strong threads, such as discussed in greater detail below, may make use of inserts or the like to provide threaded orifices, such as those discussed below.

The aforementioned cross-holes 101 extend transversely through central body portion of embodiments of members 100, 200 and 300. Cross-holes 101, are shown in FIGS. 1-3 as extending through member body 102 in only one direction. However, it is within the scope of the present systems and methods to employ members having one or more additional cross-holes extending through the respective member body, orthogonal to cross-holes 101. These orthogonal cross-holes might be either aligned with cross-holes 101, or, in the case of multi-unit members, such as illustrated members 100 and 200, disposed between cross-holes 101.

Slotted member 400 has a slot shaped cross-hole, referred to herein as a “slot” (401). Through use of a slotted member, such as member 400, off-grid component mounting holes may be flexibly addressed. As noted above, slot 401 may be of any length. Also, a member may have multiple slots, which may be of varying lengths. FIG. 4 illustrates a one unit length slot defined in a two unit long member. However, as will be appreciated from the description appearing below and illustrated in the FIGURES, such a two unit slotted member provides a versatility to embodiments of the present systems and methods, which might be enhanced in certain situations by a longer member with longer and/or multiple slots.

Embodiments of members 100, 200, 300 and 400 define bead portions 103 extending from at least a pair of corners of body portions 102 to define channel portions 104. As will be appreciated upon inspection of FIGS. 1, 2, 3 and 4, channel portions 104 are defined by a surface of body portion 102 and a pair of bead portions 103. As will also be appreciated from inspection of FIGS. 1 2, 3 and 4, bead portions 103 may extend to a position spaced from end 105 of respective member 100, 200, 300 or 400 to define key portion 106, adapted to be received in channel 104 of another member and secured thereto. Alternatively, to provide a more stable end for member 100, 200, 300 or 400, beads 103, and thus channel 104, may extend to end 105, thereby providing a greater bearing surface on such an end to better bear against a mounting structure which does not provide a channel to receive the end.

A fastener receptive orifice 107 may be defined in member end 105. Orifice 107 may be threaded to accept a screw, bolt or similar fastener. Orifice 107 may be defined by a central cannula extending through a length of body portion 102, such as may be formed during extrusion or other forming of body 102. Alternatively, orifice 107 may be defined in end 105 of body portion 102 by drilling or otherwise forming orifice 107 in the end of body portion 102.

FIG. 5 is an exploded view showing relative deployment 500 of embodiments of members of the present systems in accordance with embodiments of the present methods. In use, key portion 106 of members 100, 200, 300 or 400 may be received by channel 104 of another member, and register therewith. As illustrated in FIG. 5, key portions 106 of horizontally disposed members 501 and 502 are shown as being received by channel 104 of vertical column member 503. A screw or similar fastener 505 may be used to rigidly secure members. As shown in FIG. 5, fastener 505 may be disposed through a cross-hole (101) of one member, such as vertical column member 503, and treaded into end orifice 107 of another member, such as member 501 or 502. Lock washer 506 or a similar device may be used in conjunction with fastener 505 to insure that screws 505 do not back-out due to shock, vibration or the like. Registration between key 106 of members 501 and 502 with channel 104 of column member 503 torsionally locks members 501 and 502, relative to column member 503, in a generally perpendicular, torsionally rigid, arrangement. Further, this torsional rigidity enables the use of a single fastener (505) to secure two members together against movement relative to one another. In other words, a second fastener is not required to hold two members in position relative to one another. Although the members of FIG. 5 are shown disposed in a generally perpendicular fashion, it is within the scope of the present systems and methods that members may be disposed at an angle to one another. For example, key portion 106 of a member may be disposed at an angle relative to the axis of a member. Registration between such an angularly disposed key of a first member and channel 104 of a second member would torsionally lock the members, relative to one another, in an angularly disposed, torsionally rigid, arrangement.

Embodiments of the present systems and methods provide a strong structure for mounting instrument components. However, in accordance with embodiments of the present systems and methods members may be doubled, as shown in FIG. 6, tripled, or likewise combined, to support heavy parts mounted thereto. Two-member-truss embodiment 600 may be constructed from cord members 601 and 602, joined by spanning strut-tie members 603-606 and secured by screws 607. Components of an instrument may be secured to or on such a truss, such as by using fasteners and stand offs, or in other manners discussed herein or as known in the art, for deployment in the instrument.

Frames built using the present members may be used to mount components and circuit boards and these frames may in turn be mounted in a chassis, such as a housing or casing, which may in turn be covered or deployed as a part of a rack system or the like. In accordance with embodiments of the present systems and methods, PCBs having “off-grid” mounting holes may be mounted to one or more of the present members as illustrated in FIG. 9 below, using standoffs or the like and the members secured within a housing or case as appropriate.

Modular interlocking members 100, 200, 300 and 400, or other length members may be adapted to work with standardized equipment casing or rack systems such as AGILENT TECHNOLOGIES' SYSTEM II™ modular cabinets. For example, half and/or full housing width stretchers or beams, comprised of the present members, may be used to span a SYSTEM II™ module. Modules and frames built using the present members may be used to mount components and circuit boards within the SYSTEM II™ modules. For example, the cast aluminum front frames, rear frames, corner struts and/or side struts of the aforementioned SYSTEM II™ modules may provide structure or framework to which the present modular systems may be attached for mounting components. For a custom instrument that needs to be mounted in a test rack for example, the SYSTEM II™ front frame, rear frame and struts extending therebetween, sized for the rack that is to receive the instrument, may be outfitted with members of the present system to provide an internal structure to mount the components of the instrument, in an arrangement most conducive to operation, maintenance and modification, of the resulting instrument. The SYSTEM II™ or other standardized housing may provide covers for the instrument, if desired. However, it is well within the scope of the present systems and methods for the present elements to be used to construct the entire framework for an instrument. Further covering material such as sheet metal may be secured to the present members.

Embodiments of the present systems and methods may make use of standardized sized fasteners and unit lengths. For example, cross-holes 101 and slots 401 may be sized for three millimeter, or M3 screws, spaced at a ⅜ of an inch pitch, with end orifices 107 sized and tapped to receive such M3 screws. Cooperatively, channels 104 may be sized for the pan head of standard M3 screws, with lock washers. Thus, in this sample embodiment, a unit is ⅜ of an inch, the spacing between cross-holes 101. Such ⅜ inch spacing provides embodiments of the present systems and methods a large degree of versatility. For example, mounting hole spacings on SYSTEM II™ modular cabinet frames and the like are based on a ¾ of an inch grid.

As noted above members used in embodiments of the present systems and methods may be extruded or otherwise formed from metal, such as aluminum and steel. Such metal members may, in accordance with embodiments of the present systems and methods be used as a heat sink. The member's main body provides a substantial surface area for heat dissipation, which is increased by the member's functional features such as the aforementioned beads and unused cross-holes. In accordance with some embodiments of the present systems a member's heat dissipation surface area is comparable to, or greater than, the heat dissipation surface of a conventional finned heat sink. The cross-holes may also provide an avenue to attach heat transmission mediums and/or heat convecting surface of components.

In accordance with embodiments of the present systems and methods members may be deployed for use as a card guide. FIG. 7 is a perspective view of embodiment 700 using embodiments of members 701 and 702 of the present systems to act as a PCB or card guide. Illustrated card guide 700 is comprised of a pair of spaced apart members 701 and 702 disposed in relation to a card location in an instrument, spaced apart a distance appropriate to receive edges of card 703 and support the card in a deployed configuration in the instrument, for example, in a card slot of another PCB, such as a processor board, of the instrument.

In accordance with embodiments of the present systems and methods members may be deployed in a hinged swing assembly configuration. FIG. 8 is a perspective view of an embodiment using embodiments of the members of the present systems to act as hinged circuit board mounting structure 800. Members 801-815 are shown interconnected in an arrangement to support and mount (such as using screws, nuts and stand-offs) PCB 820. Hinge structures 822 are provided by anchor members 825, anchored to housing corner strut 830, with tubular elements 826 threadably receiving screws extending through cross-holes of anchor members 825 and screws extending through cross-holes of PCB mounting members 801 and 802. Stand-offs sized to threadably receive these screws may be used as tubular members 826. Tubular members 826, in conjunction with the screws they receive, provide a pivot for hinging of mounted PCB 820. PCB 820 and mounting members 801-815 may be releasably secured from swinging by screws (not shown) passing through holes in housing corner strut 832 into end orifices of PCB mounting members 803, 804 and 805.

Employment of embodiments of the present systems and methods for design and fabrication of an instrument, whether it be a custom instrument or a mass produced product results in an instrument that has an open structure, facilitating the routing of cables. Further, unused member cross-holes may be used to anchor cable ties used to restrain and/or route loose cabling and cable harnesses. Additionally, embodiments of the present systems and methods facilitate design changes and enhancements, as such changes and enhancements can be readily incorporated into the instrument though the addition or replacement of system members.

The present systems and methods provide significant versatility in mounting components. For example slotted members such as member 400 may be used to provide a flexibility in receiving mounting hardware for a PCB or the like. As another example, embodiments of the present systems and methods enable the suspension of components that might need airflow around them for cooling. For example, a power supply might be mounted on or suspended from a framework of members. Embodiments of the present systems and methods may also be advantageously employed in conjunction with sheet metal components that may used on a repeated basis. For example a facility that commonly used a set of switches and a few PCBs in custom designed instruments might have sheet metal components on hand that would be tailored to these components. However, the facility might employ embodiments of the present systems and methods to mount the components that vary between instruments or to provide enhanced functionality such as the aforementioned hinged PCB mount or heat sink functionality.

FIG. 9 is a perspective illustration of instrument 900 employing embodiments of the present systems and methods to mount instrument components. Illustrated instrument 900 is a switch matrix, which includes transfer switches 901. Members 902-906 are shown as mounting switches 901, with members 902 and 903 traversing instrument housing 910 and members 904-906 (with a fourth member hidden behind corner strut 911 of housing 910) extending between transverse members 902 and 903 to provide struts for mounting switches 901. Although, switches 901 may be directly mounted to various ones of members 902-906, switches 901 may be mounted to one or more preformed sheet metal parts, which in turn may be mounted to various ones of members 902-906. Strut members 904-906 may be secured to, transverse members 902 and 903 using screws extending through cross-holes of transverse members 902 and 903 and secured in end orifices of strut members 904-906. Lock washers, patch locks, or other locking mechanisms may be used in conjunction with these nuts and/or screws. This mounting of switches 901 allows for an optimal cable run to front panel 945, such as by enabling convenient and easy placement of switches 901 in close proximity to front panels 945 or in a position mid-way between two components connected to switches 901. This may also aid in avoiding cable loss and allow repositioning of the components if desired. Another strut member (912) is shown as extending from transverse member 903 to a third transverse member 913. Short members 914 and 915 are shown in use as spacers between the transverse members and strut member 912. Member 922 is shown extending downwardly from strut 912 and PCB 920 is shown as mounted to strut member 912 and member 922. PCB 925 is shown as mounted to corner struts 911 and 927 of housing 910 using members 930-933 as adapters to suspend PCB 925 between housing struts 911 and 927. Hinge structure 935, similar to hinge structure 800 of FIG. 8, is shown as mounting PCB 937 in housing 910 for swing-down access for maintenance, upgrade or diagnostics.

A beam member framework may be assembled outside of an instrument housing and components mounted to this framework, which may them be anchored in the instrument housing. Alternatively, the beam member framework may be built within the housing and then the components mounted to the framework. Embodiment 1000 of the present methods illustrated in the flow chart of FIG. 10 might be used to deploy embodiments of the present systems, such as illustrated in FIG. 9. At 1001 first beam members to be disposed in the instrument housing structure, such as members 905 and 906 of FIG. 9, may be interlocked with second beam members to be disposed in the instrument housing, such as beam members 902, 903 and 913 of FIG. 9, to provide a framework. The members may be interlocked at 1001 by keying an end (key 106) of a first beam member with a channel (104) defined by a second beam member at 1002; receiving a fastener through a cross-hole (101) of the second member into an end orifice (107) of the first beam member at 1003; and securing the fastener to torsionally interlock the members, relative to one another, at 1004. An orientation of the first beam member may be based on a desired orientation of the cross-holes of that beam member for mounting one or more components. Instrument components, such as switches 901 and PCBs 920 and 925 of FIG. 9, are indexed to and mounted to the interlocked members of the framework at 1005. The indexing might include indexing component mounting grids with the cross-holes of beam members prior to mounting. At 1006 the interlocked framework, and components mounted thereon, may be anchored in an instrument housing or the like. Alternatively, members, such as beam members 902, 903 and 913 of FIG. 9 may initially be anchored to the housing, with other beam members, such as beam members 905 and 906 of FIG. 9, interlocked with the anchored members at 1001, within the housing, prior to mounting the components on the resulting framework at 1005. Instrument components may also be mounted directly to the instrument housing structure at 1005, before or after the framework is anchored in the housing. A position of the components may be adjusted along the beam members by mounting to other cross-holes or through the use of slot members 400. To complete the instrument the mounted components are interconnected at 1007, such as through the use of cables, edge connectors and the like.

As will be appreciated upon review of the above description by one of ordinarily skill in the art, embodiments of the present systems and methods are conducive to a variety of new designs. It is anticipated by the present disclosure that as those of ordinary skill in the art use the present systems and methods for designing and constructing custom instruments, enhancements and new features not specifically disclosed herein will result.

Although the present systems and methods and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. 

1. A member comprising: a central elongated body portion; at least one cross-hole extending transversely through said central body portion; bead portions extending along at least a pair of corners of said body portion, said bead portions extending to a position along said body portion, spaced apart from an end of said body portion, to provide a key portion of said body portion; a channel portion defined by a surface of said body portion and a pair of said bead portions, said channel portion adapted to receive an end of another member and register with a key portion of said another member; and a fastener receptive orifice defined in said end of said body portion;
 2. The member of claim 1, wherein said at least one cross-hole comprises a plurality of cross-holes for indexing with component mounting grids.
 3. The member of claim 1, wherein at least one of said at least one cross-hole is elongated along a length of said member, defining a slot.
 4. The member of claim 1, wherein said body portion has a generally square cross section.
 5. The member of claim 1, wherein said orifice is threaded to threadably receive a fastener.
 6. The member of claim 1, wherein said orifice is defined by a central cannula extending through a length of said body portion.
 7. The member of claim 1, wherein said member is extruded.
 8. The member of claim 1, wherein said member is adapted to be used as a heat sink for at least one of said components.
 9. A modular system comprising: a plurality of members adapted to be interlocked with one another and anchored to an instrument housing structure, each of said members comprising: a central elongated body portion; at least one cross-hole extending transversely through said central body portion; bead portions extending along at least a pair of corners of said body portion, said bead portions extending to a position spaced apart from an end of said body portion to define a key portion at said end of said body portion; a channel portion defined by a surface of said body portion and a pair of said bead portions, said channel portion receiving and registering with a key portion of another member; and a fastener receptive orifice defined in said end of said body portion; a fastener extending though one of said cross-holes of a first of said members to be received by an end orifice of a second of said members, interlocking said first and second members and preventing torsional movement by said members relative to one another.
 10. The system of claim 9, wherein an orientation of said second member are selected based on a desired orientation of said cross-holes of said second member.
 11. The system of claim 10, wherein said desired orientation of said cross-holes of said second member are based on mounting provisions provided by one or more of said components.
 12. The system of claim 9, wherein said at least one cross-hole comprises a plurality of cross-holes indexing with a component mounting grid.
 13. The system of claim 9, wherein at least one of said cross-holes is elongated along a length of said member, defining a slot.
 14. The system of claim 9, wherein at least one of said members is adapted to be used as a heat sink for at least one of said components.
 15. The system of claim 9, wherein channels of a pair of spaced apart members are adapted to be used as a card guide for a circuit board of said instrument, said channels of said spaced apart members each receiving and retaining an edge of said circuit board.
 16. The system of claim 9, further comprising a hinge assembly, said hinge assembly comprising: an anchored member; a first fastener extending through a cross-hole of said anchor member; a generally tubular element adapted to receive said fastener in a first end; a frame member; and a second fastener extending through a cross-hole of said frame member, said second fastener received by an opposite end of said generally tubular element; wherein said frame member and any instrument component attached thereto pivots at said generally tubular member, at least partially about said anchor member.
 17. The system of claim 9, further comprising a truss, said truss comprising at least a pair of generally parallel, spaced apart, cord members arranged with channel portions of said cord members facing each other; at least one strut-tie members extending between said cord members, key portions of said strut-tie members received by said channel portions of said cord members; and fasteners extending though cross-holes of each of said cords and received by end orifices of said strut-tie members, torsionally interlocking said cord members and said strut tie members in a truss configuration.
 18. A method comprising: keying an end of a first beam member with a channel defined by a second beam member; receiving a fastener through a hole defined by said second beam member into an orifice defined in an end of said first beam member; securing said fastener to torsionally interlock said first and second beam members; and mounting instrument components to the interlocked beam members to provide an instrument.
 19. The method of claim 18, further comprising indexing component mounting grids with said beam members for said mounting.
 20. The method of claim 18, further comprising: selecting an orientation of said first beam member based on a desired orientation of said cross-holes of said first beam member for mounting one or more of said components.
 21. The method of claim 18, further comprising: anchoring said second beam member to an instrument housing structure.
 22. The method of claim 18, further comprising: threading said fastener into said orifice.
 23. The method of claim 18, further comprising: adjusting a position of said components along said beam members.
 24. A method comprising: anchoring modular beam members to an instrument housing structure; interlocking beam members disposed in said instrument housing structure with the anchored beam members; mounting instrument components to the interlocked beam members; and interconnecting said instrument components to provide an instrument.
 25. The method of claim 24, further comprising indexing: component mounting grids with said beam members for said mounting.
 26. The method of claim 24, further comprising: interlocking other beam members disposed in said instrument housing structure with the beam members interlocked with said anchored beam members.
 27. The method of claim 24, further comprising: adjusting a position of said components along said beam members. 